19 forensic science powerpoint chapter 19 forensic footwear evi

Chapter 19Chapter 19CRC Press: Forensic Science, James CRC Press: Forensic Science, James

and Nordby, 3rd Editionand Nordby, 3rd Edition 11

Forensic ScienceForensic ScienceAn Introduction to Scientific and An Introduction to Scientific and

Investigative TechniquesInvestigative Techniques

Stuart H. James and Jon J. NordbyStuart H. James and Jon J. Nordby

22Chapter 19Chapter 19CRC Press: Forensic Science, James CRC Press: Forensic Science, James

and Nordby, 3rd Editionand Nordby, 3rd Edition

Chapter 19Chapter 19

Forensic Footwear EvidenceForensic Footwear Evidence

Chapter Author: William J. BodziakChapter Author: William J. Bodziak

Presentation created by Greg Galardi, Peru, NebraskaPresentation created by Greg Galardi, Peru, Nebraska

Edited by Stuart H. James, Fort Lauderdale, Florida andEdited by Stuart H. James, Fort Lauderdale, Florida and

Dan Mabel, Richmond, VirginiaDan Mabel, Richmond, Virginia




Physical contact between footwear and Physical contact between footwear and a viable surface leaves a transfer of a viable surface leaves a transfer of class and individual characteristics, class and individual characteristics, which can be used in identification of which can be used in identification of possible suspectspossible suspects




Steps of footwear evidence collection:Steps of footwear evidence collection:• Detection and recovery of footwear Detection and recovery of footwear

evidence from scene of crimeevidence from scene of crime• Enhancing evidence as necessaryEnhancing evidence as necessary• Producing known impressions of shoes Producing known impressions of shoes

being examinedbeing examined• Comparing crime scene impression with Comparing crime scene impression with

footwearfootwear



Forms of Footwear ImpressionsForms of Footwear Impressions

• Three Dimensional Impressions – Three Dimensional Impressions – impression remaining after a shoe impression remaining after a shoe permanently deforms a surface- found permanently deforms a surface- found in sand, mud, snowin sand, mud, snow

• Two Dimensional impressions – those Two Dimensional impressions – those impressions made on tile linoleum, impressions made on tile linoleum, wood flooring etc. Some are highly wood flooring etc. Some are highly visible and others are latentvisible and others are latent



Information from Footwear Information from Footwear ImpressionsImpressions

The following information may be The following information may be obtained from footwear impressions:obtained from footwear impressions:• Identification of Footwear Identification of Footwear • Elimination of Footwear Elimination of Footwear • Participation of suspect in crimeParticipation of suspect in crime• Location of ImpressionsLocation of Impressions• Rebuttal or confirmation of alibisRebuttal or confirmation of alibis• Determination of shoe brand – FBI Determination of shoe brand – FBI

LaboratoryLaboratory



Information from Footwear Information from Footwear ImpressionsImpressions

• Linking of Suspects to the Crime SceneLinking of Suspects to the Crime Scene• Determination of Shoe SizeDetermination of Shoe Size• Number of perpetratorsNumber of perpetrators• Association with Other EvidenceAssociation with Other Evidence• Gait CharacteristicsGait Characteristics• Tracking Tracking



Location and Recovery of Location and Recovery of Footwear ImpressionsFootwear Impressions

• It is critical that proper techniques be It is critical that proper techniques be used to locate, document and recover used to locate, document and recover footwear evidencefootwear evidence

• Full and partial impressions must be Full and partial impressions must be recoveredrecovered

• Scene should be secured and evidence Scene should be secured and evidence collectedcollected




• Electrostatic Lifting – aggressive Electrostatic Lifting – aggressive technique to recover impression, technique to recover impression, normally on tile, wood, etcnormally on tile, wood, etc

• Placards or markers used to document Placards or markers used to document locations of impressionslocations of impressions

• If possible, remove and transport If possible, remove and transport impressionsimpressions




• Quality photographs should be taken of Quality photographs should be taken of impressions if they can not be impressions if they can not be transportedtransported

• Photographs are taken for later Photographs are taken for later comparison with suspected footwear, comparison with suspected footwear, therefore they must be very cleartherefore they must be very clear

• Scale should be used to gauge size of Scale should be used to gauge size of footprintfootprint



Two – Dimensional ImpressionsTwo – Dimensional Impressions

• Once an impression has been Once an impression has been photographed, the print may be able to photographed, the print may be able to be liftedbe lifted

• Electrostatic lifting transfers Electrostatic lifting transfers • Fingerprint powder in combination with Fingerprint powder in combination with

mikrosil may be used on impressions mikrosil may be used on impressions where electrostatic lifting does not where electrostatic lifting does not workwork



Three – Dimensional Three – Dimensional ImpressionsImpressions

• Dental stone is primary method of Dental stone is primary method of casting footwear impressionscasting footwear impressions

• On wet surfaces, a spray wax may have On wet surfaces, a spray wax may have to be used first to seal impressionto be used first to seal impression

• Mix dental stone with water in a ziplock Mix dental stone with water in a ziplock bag for 3 minutesbag for 3 minutes

• Stone hardens in 20 minutesStone hardens in 20 minutes• In 24-48 hours it will have fully In 24-48 hours it will have fully

hardenedhardened



Enhancement MethodsEnhancement Methods

Poor impressions may have to be Poor impressions may have to be enhanced by one of the following enhanced by one of the following means:means:• Forensic Photography – oblique, Forensic Photography – oblique,

ultraviolet, infrared or other special ultraviolet, infrared or other special methodsmethods

• Physical Methods – latent powder, lifting Physical Methods – latent powder, lifting impressions, or impressions on paperimpressions, or impressions on paper



Enhancement MethodsEnhancement Methods

Chemical Methods – reagents such as Chemical Methods – reagents such as leuco crystal violet, amido 10 black, leuco crystal violet, amido 10 black, luminol or fuschin acid may be usedluminol or fuschin acid may be used

Digital Methods – Software such as Digital Methods – Software such as Adobe Photoshop can be used to Adobe Photoshop can be used to enhance impressionsenhance impressions



Known Shoes and Preparation of Known Shoes and Preparation of ExemplarsExemplars

Footwear from Suspected Persons:Footwear from Suspected Persons:

• All footwear a suspect owns should All footwear a suspect owns should be seized for comparisonbe seized for comparison

• Shoes are needed to make test Shoes are needed to make test impressionsimpressions




• Elimination Footwear – Footwear worn Elimination Footwear – Footwear worn by police officers, medical personnel by police officers, medical personnel should be accounted for when should be accounted for when considering impressions left at sceneconsidering impressions left at scene




• Known Test Impressions of FootwearKnown Test Impressions of Footwear

• Examiner will make impressions of known Examiner will make impressions of known footwear and compare them with footwear and compare them with suspected footwear impression to insure suspected footwear impression to insure matching samples are highly detailed, and matching samples are highly detailed, and have individual characteristics of shoeshave individual characteristics of shoes



The Examination Process and The Examination Process and ConclusionsConclusions

Areas of footwear which are Areas of footwear which are examined by analyst include:examined by analyst include:• Design of shoeDesign of shoe• Physical Size and Shape Physical Size and Shape • Wear marksWear marks• Individual Identifying Characteristics- Individual Identifying Characteristics-

cuts tar, gum etccuts tar, gum etc

19 forensic science powerpoint chapter 19 forensic footwear evi

Technology

footwear chapter

impressions of known

forensic science

forms of footwear impressions

nordby chapter

crc press

test impressions chapter

transport impressions